Process for separating solids from liquids



Nov.s 4 QZQ LEBBS c. H. HAPGOOD PROCESS FOR SEPARATING` SOLIDS FROM LIQUIDS Original Filed March 25, 1922 Patented Nov.. 4l, H92@ y only/fran stares aar-saire. carica. i

GYRUS HOWARD HAPGOOD, F NUTLEY, NEW JERSEY, ASSGNOH T@ DE -LAVAL SEPARATGR COMPANY, 0F NEW YORK,'1\T. YWA CGRPORATION OF NEW JERSEY rroonss ron snranarme soLrns rnora prawns.

@riginal application filed March 25, 1922, Serial No. 546,810. Divided and this appaication led Magnat 1923. Serial No. 655,38a.

To all ifi/m t may concern Bc it known that l, CYRUS HOWARD HAP- coon, a citizen of the United States, residing at Nutley, county of Essex and State of New Jersey, have invented a new and useful improvement in Processes for Separating Solids from Liquids, of which the f ollowingis a full, clear, and exact description, reference being had to the accompanying drawings, which form a part of this specification.

lt is known to eect the separation of two ingredients in solution by reducing the temperature until onev ingredient is solfar solidilied as to throw it out of solution and then to separate the ingredients 'by filtration, settlement or centrifugal force. Examples of such processes are the separation of a1norphous wax` (petrolaturn) from cylinder oil stock, the separation of crystalline wax (paraiiine) from wax distillates, and the separation of stearin from oleo.

The most rapid, efficient, and economical method of separation is by centrifugation, but in certain yprocesses the solidified ingredient does not readily discharge from the bowl but builds up more or less on the peripheryof the bowl. Little dillic-ulty in this respect is encountered in the separation of petrolaturn from cylinder stock; ubut inthe separation of paraffin wax from wait distillates, it is necessary to blend naphtha ,withy the distillate. The wax will then discharge from the bowl, but each separated ingredient carries out with it a large proportion of naphtha and both ingredients'must be. distilled to drive olf the naphtha. This del-l eteriously 'a'ects the color of the treated material, which must be subsequently filtered to decolorize. I l

ln the separation offstearin from oleo, if the solution is subjected to\ a -temperature sufficiently low to throw Pthe stearin, in' a crystallized condition,'out of solution, the stearin can be made to discha'rge'lfr'om the bowl if there is also introduced into the bowl a heavy cushioning liquid. (e. g., water) which, in its discharge, carries with it the vcrystallized stearin.

ln a a joint application filed September 8, 1921, by Selden H. vHall and the present ycharge from the bowl. rlihis process inventor, Serial No. 499,325, is set forth a process of centrifuging refrigerated, mixtures of the above character, and specifically a process of centrifuging wax distillates without dilution or blending with naphtha, vwhich comprises feeding a liquid heavier than either of the ingredients to the periphery of the bowl so as to form a surrounding envelope ofheavy liquid, and maintaining such heavy liquid at a temperature sufficient to melt the outer layer of solids while not .sufficient to melt the vinner layer of solids, thereby allowing the melted.1 portion of the heavier ingredient to readil disdeem a substantial advance in the art, as it is not only operative but ellicient; but the specific manner of eXecution of the process set forth in said application requires the exercise of a fairly high degree of care and skill, the necessity for which is a factor obstructing the commercial success of the process.

The object of the4 resent invention is to so improve the said all and Hapgood process that theJ liquefaction of the solids adjacent the periphery of the mass of ingredients undergoing centrifugal separation and the' discharge of the so liquefied heavier, ingredient may be effected without the exercise on the part of the operator of any substantial degree of skill or more than ordinary care.

ln the accompanying drawing, the ligure isa View of a part of a centrifugal bowl shown partly in elevation and broken away to show the vremainder in vertical section and in which my improved process is adapted to be carried out.

The bowl shell/ is Adriven from the driving and supporting spindle a. rll`he bowl top c is removably secured to the shell by the flanged ring a?. The bowl top c has an inwardly extending annular ange e at its upper end. This flange is threaded to receive a removable necked Weir f.

Within the bowl is a liner g comprising a series of frusto-conical disesfo Above the liner is a top disc which, at its upper. end, has a neck z' forming a weir within, spaced from, and concentric to, and entending above, the Weir f, and without, and

concentric to, 1and spaced from, the feed 'bowl top and the bent outward and upward. The upper t be Within the bowl and adjacent its inner wall is a heatiradiator having a smooth inner surface concentric 'with the axis ofthe bowl. The radiator is preferably an annular chamber within which al adapted to circulate. As shown, this chamber is formed from an annulus of sheet metal k, the upper part of which is coneshaped to correspond to the taper of the lower part of which is edge of the sheet 7c is flanged m and secured to the inwardly extending annular .flange e of the bowl top. The opposite edge of the sheet k is flanged at n and securedto the lower part of the bowl top. Thereby is formed an enclosed chamber or compartment Z extendingY entirely around the. inside wall of the bowl. e

The [lange c of the bowl top is provided with an orifice o for admission of a heating liquid. The bowl top, just beneath the flange e, is provided with another orifice p for discharge of said liquid. Any suitable means may be provided to`insure a circulation 'of the liquid through the chamber from the inlet 0 to the outlet p, as,for example, a pipe 7 extending from the orifice o downward to near the bottom of the chamber.

Any desired number of orifices o and pipes r may be provided.

The inwardly flanged part c of the bowl top is provided on its'top with a circular ledge s,.forming a receptacle to receive the heating liquid and convey it through orifice 0 to the heating chamber. A stationary feed pipe t for heat-ing liquid discharges into this receptacle.

The top disc L is insulated, as. for example, by a layer of bakelite u, to prevent radiation of heat from the passage above it to the bowl space below it.y

The heating chamber preferably carries radial wings or blades lv, which facilitate rotation with`the bowl of its contents.

,top one being arranged to receive It is not 4imperativeI that the heating chamber shall extend down to the bottom of the bowl. The dimensions ofthe heating chamber may be varied inaccordance with variations in bowl structure and'variations in material to be heated; although if it 'be arranged as shown in the drawings, it will be adapted to practically all materials byy regulating the temperature and rate of How of the heating liquid.

Surrounding the upper part of the bowl are the usual receiving pans down which the separated lingredients flow to spouts or troughs (not shown) leading to portab-lereceiving vessels. In the present construction, there is a set of three pans, fr. y and a, the

heating fluid is the .lighterl separated ingredient, the middle one the 05 heavier, separated ingredient and the llower one the heating liquid discharged from the heating chamber. lt will be observedV that this heating liquid will discharge against the floor of the middle pan and therefore somewhat heat the separated heavier ingredient flowing down such floor, thereby still further increasing its fluidity and expediting its` discharge through the spouts above mentioned. l

Assume that a refrigerated mixture of oil and crystalline wax is fed through the feed tube 7' into the interior of thebowl and is thence distributed throughout Vthe spaces, between the liner discs. Centrifugal force operates to throw the wax outwardly while theoil is displaced inwardly. f

l It is desirable, if not necessary, to delay admission of heating fluid (say hot water) to the heating chamber until after the bowls has been filled and the materials have been divided. by centrifugal force, into an; outer zone of wax and an inner zone of oil. Heat Vexchange between the hot water and the cold the top disc h, the fluidity of the wax being the 95 maintainedin this passage by reason of extension of the radiator thereinto. The i oil will flow out through the passage within the neck of the top disc.` J

By the above means and method of heating the outer zone ot' the solidified or crystallized heavy ingredient. 'the temperature of such outer zone may be more easilyregu' lated, the .heat will penetrate to a more uni'- forni depth. and the starting of the centrifugal operation-is much easier, than if the hot liquid were introduced directly into the bowl space. The present invention also has the advantage, that the heavier ingredient isdischarged VSeparately and therefore'does not have to be subjected to any distilling or other dehydrating process.

If the invention is used of stearin from oleo. the mixture at a temperature of about ninety degrees F. in order to crystallize the stearin. The heating liquid, ywhich may be. water. should be at a temperature sufficient to melt the outer layer of ste'arin but of course not sufficient to melt the y in ner laver. S'tearin melts at a temperature of 122 degrees F. The temperature of the water as it flows into the heating chamber should be about 150 degrees F. In the case of wax distillates. the-melting points of the Various waxes vary from 100 degrees to 160,:degrees F. The water should be hot\enough to melt the wax having the A highest melting point and should, therefore,

in the separation v should be retrace@ enter the heatingJ chamberV at from 160 degrees to 180 degreesl". i f

lt is apparent that the invention is` not 'limited in its application to the separation of wax from mineral oil wax distillates, nor to the /separati'on of stearin from oleo; these two substances of widely different characteristics being cited merely as examples of useful applications of the process.,

lit is clear that the process is applicable to Athe separation of any solid from a liquid when the solid is capable of being melted.

l ain aware that the terms solid or liquid do not indicate absolute conditions, but only relative conditions, and that there is an intermediate stage of semi-solidity or semi-liquidity: lin speaking, however, oi solids undergoing separation in the bowl, l mean to imply a condition thatF is not free-flowing, as otherwise the use of my inc Vention would beunnecessary` lt will be understood' that while it is advisable, it not necessary, to maintain the surface opposedto the bowl contents at a substantially 'constant temperature during any desired operation, it may be necessary; in certain processes, to ,provide one temperature for one operation and another temperature for another operatiomwhich successive `operations may or may notttake place without stoppage of the machine. By providing (for example) heating uids of different temperatures, the. surface of the radiator may be maintained at correspondingly different predetermined temperatures.

Where, in the claims, l refer toreJ primary beating medium, l intend thereby to com- `prehend hot water' (although not be limited thereto) and intend to exclude any inter mediate@heat-transmitting medium such as the wall ot the heating chamber contacting with the wax, stearin, or other solidiied heavy ingredient. While such kwall is heated, its function as an intermediate lieatinginedium or heat transmitter is incidental, its main function being to prevent the primary heating medium from mixing or otherwise contacting with the wax or stearin and to simplity the control of the application of heat to the wax or stearin.

I do not herein claim any novel structural features herein described, as the same are claimed in an application filed by me March 25, 1922, Serial No. 546,810, of whichv this application is a division.

Having now fully described my invention, what l claim and desire to protect by Letters 'Patent is: f

1. rlihe process of separating two ingredients of dierent specific gravities which form a solution above a certain temperature and the heavier of whichsolidiiies below such temperature but at a temperature' higher than that at which the otheringredient solidifies, whichcomprises subjecting the mixture to a temperature which'will maintain the lighter ingredientV liquidand the heavier, ingredient solidfsubjecting the mixture. to centrifugation to divide the ingredients into zones, subjecting that part of `tlie heavier ingredient which during centrifugation is more remote from the lighter ingredient to the influence of a primary heating medium, regulating the temperature of said heating .medium to produce heat sutlicient to liquefy the specified part of the heavier ingredient but insuiicient to liquei'ty the part adjacent to the lighter ingredient,

maintaining said heating medium out of direct contact with the heavieringredient, and separately Howing awayv from the locus of separation the lighter ingredient and the 4`liquefied part of the heavier ingredient.

2. rEhe process of separating two ingrey dients ot' dii'erent specific gravities which form a solution above a certain temperature and the heavier of which vsolidiiies below' Such temperature but at a temperature higher than that at which the other ingredient solidies, which comprises subjecting the mixture to a` temperature which will maintain the lighter ingredient liquidnand the. heavier ingredient solid, subjecting the mixture -to centrifugation to" divide the ingredients into Zones, subjecting that part of the heavier ingredient which during cent-riitugation-A is more remote from the lighter ingredient to the infuence et a primary heating medium, regulating the temperature of said heating medium to produce heat sufiicient to liquefy the speciiied/ the pointer discharge, and maintaining said I heating medium out of direct contact with the heavier ingredient while in the locus of separation and during its passage toward the discharge.

3. The process of centrifugally separating two ingredients of different specific gravities which form a solution above a certain 'temperature and the heavier oit which solidiiies below such temperature but at 'a` temperature higher than that at which the other ingredient solidifies, a mixture of which' has been subjected to a temperature` which will maintain t-he lighter ingredient liquid and the `heavier ingredient solid, which ponipri'sessubjecting the mixture to centrifugation to divide the ingredients into zones, separatelyr owing away from the locus of separa-tion theA lighter ingredient and the heavier ingredient. discharging the heavier ingredient from'the centrlfuge at a point distant from the locus of separation, subjecting the outflowing heavier ingredient to the influence of 'a primary heating medium in its passage from the locus of separation to the point of discharge and maintaining said heating medium out of direct vcontact with the heavier ingredient'.

4. The process of centrifugally separating two ingredients of different specific grav.

:ities which form a solution above a certain temperature and the heavier of which solidifies below such temperature but at a temperature higher than that at which the other ingredient solidifies, a mixture of which has been subjected to va temperature which will maintain the lighter ingredient liquid and the heavier ingredient solid, which comprises subjecting the mixture to centrifugation todivide Ithe ingredients intd zones, separately flowing away from the locus of separation the lighter ingredient and the heavier ingredient, discharging the heavier ingredient from the centrifuge at a point distant from the locus `of separation, heating the. discharge passage while excluding admission theremto of a foreign liquid, and delivering the heavier ingredient from the centrifuge without admixture with a heated liquid from Vwhich it must be separated.

5. The process of separating two ingredients of different specific gravities one of which is in a liquid state and the other of which is solidified, which comprises sub- .clients of different jecting the mixture to centrifugation to divide the ingredients into zones, subjecting that part of the'solidified ingredient more` remote from the liquid ingredient tothe action o f a flowing stream of fluid suflicient- 1y hot to liquefy suchV part, maintaining the heating fluid out of contact with the vpart of the solid undergoing liquefication, and. flowing off separately the ingredient that has been so liquefied,

that had not been solidifed, and the heating fluid 6. The process of separating two ingrespecific gravities one of which is in a liquid state and the other of which is solidified, which comprises subjecting the mixture to centrifugation to divide the ingredients into zones, flowing off' separatelythe two part of the solidified ingredient more remote from the liquefied ingredient andina the locus of separation, and also the-heavier ingredient in its passage to fthedischarge, to the actionl of a flowing stream of fluid sufficiently hot to liquefy such in edient, and maintaining -said heating ui out of contact with such ingredient while the latter is in the locus of separation and during its dlscharge,

that will solidify the wax insufficient to Athat will solidify the wax the other ingredientl f ingredients, subjecting that' terasse 7. The process of separating two ingredients of different specific gravities one o which is in a liquid state and the other of which is solidified, which comprises subjecting the mixture to vide the ingredients into zones, separately the two ingredients, subjecting the heavier ingredient in its passage from the locus of separation to the point of discharge to the heating action of a flowing stream ofjfluid sufficiently hot to prevent clogging in the discharge passage, and maintaining tact with the heavier ingredient.

8. The process of separating a solution of mineral lubricating oil and wax which comprises subjecting such solution, in a substantially undiluted form, to a temperature and throw it subjecting the mixtureto cenout of solution,

divide the ingredients into trifugal force to centrifugation yto diflowmg ofil` an outer zoneof wax and an inner zione of oil, subjecting'that part of the wax that during centrifugation is more remote from the oil to the influence of a primary heating medium, regulating the temperature of such au u heating `medium to produce heat 'sufficient i to liquefy the specified part of the wax but liquefy the part of the wax adjacent to the oil, maintaining said heatino' mediunt out of-contact with the wax, and separately flowing away from the locus of separation the oil and the liquefied part of the wax.

9. The process of ,separating a solution of vmineral lubricating oil and wax which comprises subjecting suchsolution, in a substantially undiluted form, to a temperature and throw it out of solution, subjecting the mixture to centrifugal force to divide the ingredients into an outer zone of wax and an inner zone of oil, subjecting that part of the waxthat 'during centrifugation is more remote from the-oil'to the influence of a primary heating medium, regulating the temperature of such heating medium to produce heat sufficient vto liquefy the specified part of the wax but insufficient to liquefy the part of the wax adjacent to the oil, separately flowing away from the locus of separation and discharging the oil and the liquefied part ofthe wax, subjecting the outflowing liquefied wax to the influence of a primary heating medium Jin its passage from the locus of separationto the discharge, and maintaining said heating medium out of contact with the wax while in the the locus of separation and during its passage toward the discharge. j

10. The process of separating a solutionof mineral lubricating oil and wax which comprises subjecting such tially undiluted form, to a temperature that will solidify the Wax and throw it out of solution,l S .bjectng the mixture to centrifusolution, in a substan-I El@ i :19a-ism@ @i gai nrc@ to divide the ingredients into an maintaining said heating medium out of i@ outer zone of Wax and an inner Zone of nii9 difeca Contact with the wax.

separately iicwing away from wh@ locus of in testimony of which invention, have Separation the Wax and @ilj disharging 'the hereunto set my hand, at New York, on this Wax from the centrifuge at a point distan?, 31st day of July 1923. from the locus of spnmtion, subjecting the CYRUS -WARD HAPGD- outflow/ing Wax to die inuence 0I a primary Witnassesz heating medium in its passage from the locus JOHN G. PAUL,

of se mation to the mint of dischmr e sind GEO. D. TALLMAN. 

